摘要:目的:观察累加电针对炎症痛大鼠模型不同间隔时间的镇痛效果,从而探讨针刺镇痛的最佳治疗间隔时间。方法:96只雄性SD大鼠随机分为正常组、模型组和电针组,以佐剂性关节炎大鼠作为炎症痛模型,分别以3、6、12、24h作为电针治疗间隔时间。选用“昆仑”和“悬钟”穴,电针频率15100Hz,疏密波,电压2100Hz,疏密波,电压24V,留针20min,连续治疗6d后观测大鼠疼痛级别、痛阈、下丘脑前阿黑皮素和前脑啡肽原mRNA的表达。结果:电针组的疼痛级别明显低于模型组(P<0·05),24h电针组的痛阈高于模型组(P<0·01),各电针组下丘脑前阿黑皮素和前脑啡肽原mRNA表达的细胞数均明显高于模型组。在不同间隔时间电针治疗中,以间隔24h治疗更能明显降低炎症痛大鼠的疼痛级别并提高其痛阈,促进下丘脑前阿黑皮素和前脑啡肽原mRNA表达(P<0·05或0·01)。结论:电针对炎症痛大鼠模型具有非常明显的镇痛作用,间隔24h重复治疗可显著提高其镇痛效果。Objective: To observe the analgesic effect of repeated electroacupuncture (EA) with different intervals in a day in adjuvant arthritis (AA) rats so as to find the best time interval of EA for analgesia. Methods: A total of 96 SD rats were evenly randomized into normal, model and EA groups which were further divided into 3 h , 6 h , 12 h and 24 h subgroups, with 8 cases in each subgroup. AA model was established by subcutaneous injection of Freund’s Complete Adjuvant ( 0.1 mL ) into the right hind paw. EA (15/ 100 Hz , dense-sparse waves, 2- 4 V ) was applied to the right “Kunlun” (BL 60)-“Xuanzhong” (GB 39) for 20 min every time, with intervals of 3 h , 6 h , 12 h and 24 h everyday and continuously for 6 days. The pain grade (according to Xu’s method4V,留针20min,连续治疗6d后观测大鼠疼痛级别、痛阈、下丘脑前阿黑皮素和前脑啡肽原mRNA的表达。结果:电针组的疼痛级别明显低于模型组(P<0·05),24h电针组的痛阈高于模型组(P<0·01),各电针组下丘脑前阿黑皮素和前脑啡肽原mRNA表达的细胞数均明显高于模型组。在不同间隔时间电针治疗中,以间隔24h治疗更能明显降低炎症痛大鼠的疼痛级别并提高其痛阈,促进下丘脑前阿黑皮素和前脑啡肽原mRNA表达(P<0·05或0·01)。结论:电针对炎症痛大鼠模型具有非常明显的镇痛作用,间隔24h重复治疗可显著提高其镇痛效果。